SEA DRAGON CLASS NUCLEAR ATTACK SUBMARINE
KAIRYU SSN
COST (UNIT): 1 800 000 000 N$D
COST (DPR): 180 000 000 000 N$D (SACTO/ALLY RESTRICTED!)
- Length: 125 m.
- Beam: 14 m.
- Draught: 8.1 m.
- Displacement:
- Surface: 8 500 t.
- Submerged: 13 000 t.- Propulsion: Single KJ - XII Lead-cooled fast reactor and 1x waterjet.
- Speed: 36 kn (max submerged) / 28 kn (max submerged silent) / 19 kn (max surfaced).
- Range: Unlimited by fuel, but limited to food supply.
- Endurance: 100 days.
- Test Depth: - 700 m (with damage to electronics).
- Crew: 98 (including 32 officers).
- Sensors:
- Washi Passive/Active Sonar 1830 networked system.
- Funryu Type 2 Mark 2 Model 1 radar.
- 2x Funryu F1 optronics mast.- Countermeasures:
- WaShi WSC - 03 tube fired acoustics decoy
- Murakami MSC - 8 sonar intercept receiver.
- Murakami IFF - 21.- Armament: 4x 533mm torpedo tube, 4x 650mm torpedo tube, 16x VLS for 32 NY-4, SAMast 8.
Sea Dragon Class (Kairyu in Nifonese) nuclear attack submarine, also known as Xray II class nuclear attack submarine by the codename that was given to it by western navies, is a Nifonese SSN (Submersible Ship Nuclear), a designed as first of new Kairyu series to replace SSN from Nifonese navy. Major task of this enormous warship is to combat enemy aircraft carriers, as well as enemy submarines. It already has been nicknamed by many navies "Nifonese Black Hole" due to the fact that it is most quiet of Nifonese submarines yet built.
Hull:
"Sea Dragon" is using two-hull design, composed of two hulls, second inside the first one. The task of inner pressure hull one is to withstand water pressure while the majority of protection against mechanical damage is provided by hydrodynamic (outer) hull. Shape in which Kairyu was shaped into was designed to provide minimal acoustic signature and minimal water resistance. To allow the Kairyu to break through the tick ice on the Northen Furukuran sea, cover of the sail was additionally reinforced while the sail itself has been reduced in height for length and also houses a radar mast, two optronic/periscope masts (one for commander, one for crew), communications mast and navigation mast, mounted on top of it. Just below the sail are mounted twin front horizontal hydroplanes, which are generally short and are able to be retracted into the hull should need arise. At the rear of the submarine are four pitch to turn fins, with upper one possessing increased bulb housing the towed array.
Both hulls are separated by about 3.5 m thick space, argumentation buoyancy and survival ability. The component used in building the hull is titanium, with additional cover of anechoic tiles. While seriously increasing costs, titanium provides the submarine with amazing resistance to magnetic anomaly detection (MAD) and water pressure. In 2014 a team led by Cpt. Hashimoto from the 2nd Home Fleet of Kaigun conducted tests on one of prototypes, descending on 700m and successfully surfacing. While such feats are uncalled for, they prove how durable this submarine is. After that to add to the protection and increase security of the crew the hull was divided into seven autonomous compartments separated from each other by titanium walls, from which one serves as crew living quarters, and one as operations center, another houses the reactor, engine, etc. Only those two sections are traditionally manned, which allows the modular design to provide far increased chance for crew to survive impact of eventual torpedo or some accident.
Forward part of the hull houses enormous WA 29 passive sonar which due to it's sheer size forced moving the torpedo tubes backwards, just below the sail. Additionally Kairyu was equipped with several VLS tubes fitting for various types of missiles.
Propulsion:
"Kairyu" is propelled by a single KJ - XII IVth generation lead bismuth fast reactor with 210 MW power mounted within it's hull, using a mixture of lead and bismuth as heat exchange material instead of water. KJ - XI operates on closed fuel cycle, which allows it to have enormous lifespan (over 30 years). Lead works as excellent gamma ray shield, deflecting neutrons escaping the core. The reactor features series of innovative solutions that allowed it to function properly; to prevent corrosion of elements drowned in molten lead, core mean outlet operates at reduced temperature of just 480* and all mechanism are outside the coolant. Aluminium was chosen as material for heat transfer surfaces. To counter the issue posed by large mass of lead, the reactor vessel has been made shorter, thus dispensing the weight (which forced increase of weight of the submarine itself, but to considerable extent). As material to generate the power, enriched uranium-225 is used. KJ - XII reactor, while a bit costly, offers a lot of advantages over traditional water - cooled nuclear reactor, although posing also some potential problems. One of major advantages is the ability to change whole core instead of refueling it, which increases lifetime of KJ - XII and reduces costs of operating at the same time - especially recommended for countries with lack of nuclear infrastructure on their own. In addition Lead Bismuth fast reactor is much safer than water - cooled reactor since it can't cause explosion because lead quickly solidifies in cause of leak, thus preventing the potential explosion and does not require electricity to cool it down after shut-down. Major problems however with this reactor are the solidifying of lead, making KJ - XII require constant maintenance by qualified personnel. Another issue can be bismuth's transmutation to highly radioactive Polonium, which has however been highly reduced by high automation of the reactor operations. In addition upon order there is a chance to replace KJ - XII with another reactor of the client's choice, which however will require extra costs to cover design changes.
Main propeller of the Kairyu is a pump jet propulsion system which holds the propeller blades pressurized, greatly decreasing cavitation thus decreasing level of noise that submarine emits, increasing the speed on which submarine may still uphold the stealth needed for the operation. It has to be noted that the one mounted on KR487, designed by Washi, resembles more jet engine than a conventional submarine screw - based propeller. It's major component is an enormous cylindrical shroud housing inlet and outlet, covering a rotating hub to which the blades are attached and a stator. Entire system is powered by a powerful electric motor that spins the propeller blades around. Several support vanes are responsible for connecting the shroud to the rotating propeller and keeping the structure together. This sort of propeller provided Kairyu with several advantages, such as reduced noise due to the fact that shroud posseses extremely well developed noise - blocking capabilities. Due to the fact that flow of the water is mostly unencumbered, the propulsion of the Kairyu possesses far better thrust output while maintaining good stealth capability.
Sensors:
Major sensor of the Kairyu is Washi Passive/Active Sonar 1830, which is a self sustaining sonar system in which submarine is equipped consisting of roughly about 14 000 hydrophones from various subsystems consisting the P/AS 1830, which are:
- Single WA 29 bow mounted spherical passive / active sonar, notable for it's enormous size which was cause of the submarine's torpedo tubes being pushed backwards. The enormous sonar provides multiple functions such as broadband detection, automatic target tracking, audio recording, TMA (target motion analysis), target identification or torpedo warning. The sonar operates on frequency between 0,3 kHz to 12 kHz and provides 0,5* bearing accuracy in ideal conditions. The enormous sonar is more than capable of tracking quiet targets at even long ranges. Range is up to 120km.
- Two WA 31 very low frequency active sonar mounted in blow and sail, operating on bandwidth of 8 to 12 kHz. Due to ability of VLF emissions to easily traverse waves, chance to detect enemy at far longer range was significantly increased.
- Two side WA 38 flank array sonar systems operating on high frequency, for observing targets on the sides of the submarine, built out of operating on bandwidth below 3200 Hz is composed of ultra - thin panels and features very efficient system responsible for filtering out submarine's own noise. Bearing accuracy is approximately 1*.
- Single WA S2 is a very low frequency towed array sonar mounted in structure on submarine's top fin operating in bandwidth between 100 and 1600 kHz providing 360 degree coverage for the submarine. Capable of being deployed at maximal speed of 12 knots for 10 minutes, and itself being maximum 120 meters in length this very thin towed array suite works increasingly well in both oceanic and deep sea environments. Bearing accuracy is roughly 0,5*.
- Washi Echo sounder 1515, responsible for measuring the distance between submarine and bottom of the sea.
- WA 44-1 is a mine and obstacle avoidance sonar operating on bandwidth of 70 to 100 kHz with 120 horizontal and 90* vertical degrees scan area.
- Funryu Type 2 Mark 2 Model 1 is a non - hull breaching mast housing radar operating in I - band. The antenna itself features end fed slotted line array and horizontal polarization. Another important features are low electricity consumption, low signature and short - medium pulse lengths. Funryu can track up to 50 targets, and possess target acquisition capability argumented by selectable zone mode.
-Funryu F1 is an non - hull penetrating optronic mast currently in use on Kairyu incorporating a whole array of sensors used to detect enemy platforms which include thermal IR, true HD imagining CCTV and ESM systems mounted inside. Responsible for wide range of observation is mounted on 3d stabilization axis. Mast is equipped with an Advanced Man / Machine interface which makes it simple to use and provides quick data analysis on demand. Due to structure possessing low RCS / acoustic and visual signatures, the mast can easily be employed without revealing the submarine's location. Maximal employment speed is 12 knots, 16 is maximum survival. Two such masts are mounted on kairyu, one for Captain and one for the crew.
Additionally the submarine is equipped with Murakami MSC - 8 sonar intercept receiver capable of detecting both single and multiple sonar pulse from over 90km distance at 5 kHz frequency, and an IFF (IFF - 21) system built by the same company.
Control System:
The submarine is equipped with newest control systems built by Washi, which were created to ensure maximum automatisation. The systems include:
- Washi Hamoni-12 command and control (C2) system gathering and processing data from all important components of submarine. Hydroacoustics, radars, optics, ESM, navigation and other important systems are being gathered and processed through this system. On basis of this data the system can determine exact speed, trajectory and distance of target. The data are display on LCD screen on the bridge, alongside with other control terminals.
- Sogeki - Hei 8 weapon control system for command and control (C2) of the attack. Sogeki - Hei 8 has both the cruise missiles, torpedoes and counter - measures linked to it and can be used in both manned and automatic version.
- Washi Fukai 2 navigation and course control system. Fukai 2 is capable of controlling the speed, depth and course as well as planing and executing, both manually or automatically, advanced maneuverers.
- Washi Doramu 5 is capable of gathering and processing information, as well as controlling all machinery mounted on the KR487 submarine, reducing manning of the reactor and other machinery to minimum and allowing to reduce amount of crew present on ship.
- Washi Rosoku 3 a radiation monitoring system capable of gathering and processing information about state of the reactor and radiation it emits.
- Yamakusa Y7F1 telescopic communications mast is a telescopic submarine antenna operating on high frequency (HF) between 10 kHZ and 30 mHZ and with maximum input power of 0.5 kW. The mast can be extended to 4,4 meters (when collapsed) and 7,5 meters (when fully extended). Built from epoxy glass fiber with naval brass metallic parts as one - part design, Y7F1 proven itself to be highly resistant, corrosion - free and reliable. Maximum expansion speed is 13 knots, the mast depth
New addition to the submarine's intelligence gathering capabilities is the Yamakusa Kagekame (Shadow Turtle) multi purpose buoy, designed especially for high - threat environments, where likeness of submarine's detection is enormous. Kamekage is connected to the submarine with two - way fiber optic cable, providing swift transfer of data, and can be equipped with multiple devices, including, but not limited to, communications devices, electronic warfare gear, AXISAT positioning system or TV/IR camera for observation of surface contacts at any time of the day, etc. To minimize the chance of detection, main body - being about a 1.6 meter tall and one in diameter - was optimized for low RCS and low wake signature, usually being pained in dark blue colour to avoid contrasting with the sea, even though only top part - roughly several centimeters - actually finds itself above sea level. Successfully recovery tests have been performed on speed as much as 4 knots. Communications variant can sustain as much as 2200 ping seconds of transit using lithium - ion batteries after being detached and operates on frequency of 1.8 kHz. Other choice in communications buoy involves Yamakusa 8P2 communications buoy, which is a towed, expendable two way communications buoy operating usually at 1.8 kHz frequency to communicate between submarine and land based systems. The buoy itself is only 25 centimeters in length when combined with the submarine launch vehicle (SLV). Being able to be deployed from as much as 250 meters, 8P2 heads up to the surface where it can remain active for 72 hours of operation or 1800 total ping seconds of transmit using lithium batteries. Total custom programming capability allows the operator to set up the broadcast at time when the submarine will be far away, denying the enemy chance to detect it's location, with expandable cable connecting the submarine to buoy extending for several miles. This system is extremely important for any submarine, due to ability to transmit data between the C4ISTAR assets and the launch platform. Both systems can be easily attached to the sail or deck without disturbing the structure in any way.
Armaments & Countermeasures:
Main armament of "Sea Dragon" are eight torpedo tubes mounted behind the sonar array. The submarine possesses 4x 533mm tubes and 4x 650mm tubes (the last ones serving to sink heavier warships). This allows the Sea dragon class to launch variety of ASuW and ASW torpedoes, missiles such as Harpoon or mines, successfully allowing the ship to partake in mine warfare operations. It is estimated that the submarine can carry around 38 missiles and torpedoes ready to be tube launched.
The ship is also equipped with 16 VLS tubes that can incorporate wide range of weaponry - packing - usually 32 "Great Moon" missiles.
In addition Kairyu is equipped with SAMast 8, a mast with a box launcher for 4 Type 5 Rakurai MANPADS coupled with an IR camera, allowing the submarine to fire them from under the water, engaging eventual ASW helicopters.
The submarine is also equipped with system of acoustic countermeasures mounted in special tubes on the fins and within the superstructure, called WaShi WSC - 03. The system is composed of the launchers releasing so called effectors into the water, as well as an integrated Command & Control system that automatically detects the torpedo, calculates safest escape route while at command releases the countermeasure. Codenamed WS - M - 7, said countermeasure is stored externally and launched on operator's command. 100 mm in diameter and 1100mm long, WS - M - 7 moves onto depth pre - selected by the operator via it's own contra - propeller motor, then hovers on said depth. Equipped with an acoustic projector, WS - M - 7 causes the enemy torpedo to "see" multiple false targets forcing it to home on them, allowing the real submarine to escape. Being completely user programable, WS - M - 7 can be programmed for any mission until the launch, then it executes the task and falls onto the bottom of the sea once it is completed.